Simplify the following expression: $k = \dfrac{40p + 10n}{10p + 10} - \dfrac{40n - 50}{10p + 10}$ You can assume $m,n,p \neq 0$.
Solution: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{40p + 10n - (40n - 50)}{10p + 10}$ $k = \dfrac{40p - 30n + 50}{10p + 10}$ The numerator and denominator have a common factor of $10$, so we can simplify $k = \dfrac{4p - 3n + 5}{p + 1}$